JPS615848A - Bobbin for blood dialytic hollow yarn - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention mainly relates to a bobbin wound with hollow fibers for making a hemodialyzer.

In this invention, the word "bobbin" also includes the meaning of cheese.

Hemodialyzers using hollow fibers have been widely used in medical care in recent years to replace the functions of kidneys, liver, etc.

A characteristic of a hemodialyzer is that blood is circulated within the hemodialyzer, so it is better to minimize the amount of blood filled in the dialyzer. In addition, for example, in the case of patients with chronic kidney disease, hemodialysis is performed continuously two to three times a week, and each time, hemodialysis is performed for a long time, 5 to 8 hours, so that the blood can be efficiently treated. Dialysis must be performed. In currently developed hemodialyzers using hollow fibers, for example, in the case of artificial kidneys, a bundle of hollow fibers with an inner diameter of 100 to 1000 μm is placed in a container with a length of 150 to 300 μm. The hollow fiber bundle is tightly packed and both ends of the hollow fiber bundle are adhesively fixed with an adhesive such as urethane resin. By passing blood through the inside (hollow part) of the hollow fibers of this hemodialyzer, and flowing dialysate whose osmotic pressure is approximately the same as that of the blood outside the hollow fibers, water, urea, creatinine, uric acid, etc. in the blood are removed. Waste products are removed, but in this case, it is important to improve the dialysis efficiency of the hemodialyzer.

The present inventors have discovered that in order to improve the dialysis efficiency of a hemodialyzer using hollow fiber bundles, the dialysis efficiency can be increased to some extent by independently imparting crimps to each hollow fiber. As a result of further study, we found the best means for imparting crimps to hollow fibers for hemodialysis and arrived at the present invention.In other words, the present invention is based on the method of winding 3 to 10 hollow fibers used for hemodialysis in a twisted state. The present invention provides a hollow fiber bobbin which is formed by removing the fibers, and its use increases the dialysis efficiency described above.

Hollow fibers used in the present invention include cellulose acetate, cuprammonium cellulose, polyacrylonitrile, trimethyl methacrylate, polyethylene,
Hollow fibers such as polyvinyl alcohol can be suitably used.
The inner diameter of the hollow fiber used is 100 microns to 10
Oo microns are suitable.

In the spinning process (including spinning, coagulation, water washing, glycerin treatment, and drying process), a plurality of hollow fibers of 3 or more and 10 or less are combined at a winding angle of 5° or more and wound around a bobbin for 30 minutes.
By employing a method of heat treatment at a temperature of .degree. C. or higher and 200.degree. C. or lower, the combined hollow fibers mutually reinforce each other and prevent the hollow fibers from becoming bulgy, thereby imparting an appropriate crimp. That is, if the number of hollow fibers to be combined exceeds 10, the shape of the bobbin will deteriorate and at the same time the crimp effect of the present invention will be weakened. On the other hand, if the number of hollow fibers to be combined is less than three, the crimp effect will be stronger, but the cross-sectional shape of the hollow fibers will be deformed.

The hollow fibers that have been spun and wound onto a bobbin are normally wound on a winding machine and then processed to produce modules. By using a plurality of hollow fibers of this size or less, the yarn strength of the bundle of hollow fibers can be increased compared to the case of using single-filament hollow fibers. As a result, it was possible to increase the winding speed of the take-up machine and improve productivity and operability.

This becomes even more effective particularly when hollow fibers with low fiber strength are used. Furthermore, by doubling a plurality of hollow fibers, it is possible to increase the number of hollow fibers to be wound at one time, and from this point of view as well, the productivity of the winding machine can be increased. Normally, 2oo.

A module is made by bundling one or 100,000 hollow fibers, but especially in the case of hemodialysis modules, even one hollow fiber in the bundle of hollow fibers may be damaged. The module becomes unusable. In this case, if the hollow fibers are used as a bundle of 3 or more and 10 or less, the hollow fibers will reinforce each other and will not cause damage to the hollow fibers.

The present invention can be applied not only to hemodialysis but also to hollow fiber bobbins for use as dialysis equipment for industrial applications such as hemofiltration, plasma separation, and skim milk concentration.

Examples of the present invention will be described below, but the present invention is not limited to the same extent by these Examples.

Reference Example A cellulose acetate hollow fiber having an inner diameter of 200 μm and an outer diameter of 244 μm was wound onto a bobbin. When winding this bobbin, the contact pressure and tension were changed as shown in Table 1, and when the bobbin was left for 48 hours after winding, it was found that increasing the contact pressure and tension had no effect on increasing the crimp number. I couldn't wait. Also, if the tension was increased too much, both ears of the bobbin would stand up, causing the bobbin to become malformed. The crimp number referred to here refers to the number of peaks (or valleys) of the hollow fiber that can be seen when the hollow fiber cut into looms is placed on a flat plate.

Table 1 Examples and Comparative Examples Next, the spun cellulose acetate hollow fibers (4 yarns) were wound onto a bobbin (tension: 59, contact pressure: 500 mm).
After being left for 8 hours, it was heat treated at 60'O for 18 hours. In this case, the number of crimps in the four-ply hollow fiber bundle is
Shown in the table. For comparison, a bobbin with two yarns was similarly heat treated and the number of crimps was examined.

The results are also listed in Table 2. From the results, it was found that the number of crimps made with four yarns could be approximately doubled compared to the two yarns. Comparing these results with Table 1, it is found that by combining the doubling conditions with the heat treatment, the crimp effect can be greater than simply increasing the contact pressure or tension and leaving the wound bobbin alone. did it.

Table 2 Furthermore, when we compare the tension of the hollow fibers of the double yarn and the single yarn, as shown in Table 3, the tension of the hollow fiber with four double yarns is about four times that of the single yarn. became. As a result, the winding speed of the hollow fiber from the bobbin was changed from 1 Ova7=n in the case of a single yarn to 35 m1m in the case of a 4-ply yarn, which caused damage to the cross-sectional shape of the hollow fiber. Without giving (,3,i5 times).

Cellulose acetate hollow fibers (6 fibers) after dry spinning were wound onto a bobbin and left for 18 hours at 60°C.
Heat treatment was performed for 18 hours. FIG. 1 shows the crimp form of a six-ply hollow fiber bundle. Also, Figure 2 shows a hollow fiber bundle that is not crimped.Table 3

[Brief explanation of the drawing]

FIG. 1 is a schematic view showing the crimped state of the hemodialysis hollow fibers according to the present invention, and FIG. 2 shows a hollow fiber bundle that is not crimped.

Claims (1)

[Claims] Three or more hollow fibers used for hemodialysis and 10
A bobbin for liquid dialysis hollow fibers, which is formed by winding a plurality of threads of the same size or smaller in a doubled state.